wright



March 22, 1955 c. E. WRIGHT 2,704,477

CENTERING AND GUARD SPRING FOR PIPE WRENCHES Filed Sept. 13, 1952 2Sheets-Sheet 1 INVENTOR.

6 ,4 TI'OPNE Y March 22, 1955 c. E. WRIGHT CENTERING AND GUARD SPRINGFOR PIPE WRENCHES 2 Sheets-Sheet 2 Filed Sept. 15, 1952 dill] INVENTOR./yq e 5 M1? United States Patent CENTERING AND GUARD SPRING FOR PIPEWRENCHES Clyde E. Wright, Elyria, Ohio, assignor to The Ridge ToolCompany, Elyria, Ohio Application September 13, 1952, Serial No. 309,429

4 Claims. (Cl. 81-101) This invention relates to improvements in pipewrenches and more particularly to an improved hook jaw centering springfor pipe wrenches.

It has become common practice to provide in a pipe wrench, a handlewhich carries at one end a heel jaw and at the same end, offset thereto,a housing having an opening through which a hook jaw extends. It isdesirable that the hook jaw move both forward and backward over the heeljaw in order that the proper ratcheting and gripping action with thepipe may be realized. In accomplishing this, the housing opening isusually wider toward the heel jaw end and the hook jaw pivots about acenter at approximately that end of the housing remote from the heel jawend, a nut being threaded on the shank of the hook jaw and bearingagainst said remote end of the housing.

In recent years it has been customary to make the handle and housing,which are integral, of the softer and lighter metals, such as aluminumor magnesium. In these instances the hook jaw, being of steel, has atendency to wear the housing, and the nut has a tendency to dig into andmutilate the housing.

The present invention contemplates a spring construction which of itselfpresents an improved construction easier to make and resistant tobreakage. It also guards the inside of the housing against wear from thehook jaw as well as guards against wear from the nut, and provides aresultant distribution of pressure from the nut to the housing over alarge area, which pressure would otherwise be localized.

Still other advantages of the invention, and the invention itself willbecome more apparent from the following description of an embodimentthereof, which description is illustrated by the accompanying drawingsand forms a part of the specification.

In the drawings:

Fig. 1 is an elevational view of a wrench of this invention with thehousing and handle partly broken away and shown in section to showcertain parts which would otherwise be hidden;

Figs. 2 and 3 are side elevational views of the centering springs usedin the housing;

Figs. 4 and 5 are face views thereof; and

Fig. 6 is a bottom plan view of one of the springs.

Referring now to the drawings, throughout which like parts aredesignated by like reference characters, and particularly to Fig. 1wherein there is illustrated a pipe wrench which includes a handle 10,the upper end of which is provided with a heel jaw 11, held in place bya pin 12 in a manner well known in the art.

The portion to the left will be considered the front, and the part tothe right, the back, of the wrench.

Extending backward at the upper end, as viewed in the figure, is a hookjaw housing 14 which is cast integral with the handle. The hook jawhousing is provided with an opening 16 which extends substantiallyparallel with the handle through the housing from top to bottom. Theopening is of generally rectangular cross section, being wider at thetop than the bottom, and the front and rear walls are provided withgrooves 17 and 18 respectively.

The opening is adapted to receive a hook jaw which includes the toothedportion 20 that overhangs the heel jaw and a shank part 21, of generallyrectangular cross section, which extends through the opening and isprovided with threads 22 on the front and rear edges upon which isthreaded an adjusting nut 23.

Spaced below the housing is a pair of ears 24 between ice which theshank may slide and which serves as an abutment for holding the nutagainst movement longitudinally of the housing.

The hook jaw, because of the shape of the opening in the housing, iscapable of a limited amount of forward and backward movement over theheel jaw. This enables a better and quicker grip to be obtained on apipe as well as to allow the ratcheting engagement of the jaws with thepipe in a manner well known in the art.

In order to provide the most efiicient of such action, it is preferablethat the hook jaw shank be centered in the opening so that from thisposition it can move either way.

In this case, this is effected by two improved springs of the invention,one being interposed between the inner wall of the opening in thehousing and the front side of the shank, and the other being disposedbetween the rear edge of the shank and the back wall of the opening.

The springs are alike except for length, the one on the front sidepreferably being longer because that wall is longer, and the one in backbeing shorter because the back wall is shorter due to the taperedcontour of the v housing which can best be seen in Fig. l.

As can best be seen in Figs. 2 and 4, the spring for the front wallincludes a semi-circular base 30 which provides a washer like guardbetween the nut and the lower surface of the housing, it being notchedat 30' to allow the hook jaw shank to pass therethrough. The diameter ofthe base is substantially equal to the diameter of the nut but maypreferably be somewhat larger.

Extending upward from and normal to the base is an upright member 31which is curved transversely (Fig. 6) in an arc of substantially thesame radius as the periphery of the threads 22 on the shank of the hookjaw. This member is adapted to lie against the face of the hook jawshank and besides guiding the hook jaw shank, prevents the threads ofthe hook jaw shank from digging into the housing wall.

The upper end of the upright 31 is bent outwardly at 32 which isdesirable to enable easier assembly of the hook jaw shank in thehousing.

It can be seen that, since the base of the spring is enlarged betweenthe nut and the bottom of the housing, the hook jaw shank is heldcentered in the housing. This centering action is, however, assisted bya tongue 33 struck from the center part of the upright and which tongueis bent outward away from the upright and seats in the groove 17. Theend of the tongue is curved at 33 away from the groove wall.

The other spring is as stated exactly the same except for length. It hasa base 35, upright part 36, and a tongue 37 which is bent at 38.

It will be appreciated that the structure of both springs lends itselfto a simple stamping operation from a single sheet of metal, which ispreferably of some highly resilient metal such as spring steel. It willalso be apparent that a dual spring action is present due to each springbase being engaged between the nut and the housing and each springtongue extending into the groove in the adjacent housing wall. It is tobe particularly noted that greater strength for each spring is realizedbecause each upright member is completely closed, being formed by twoside strips integral with a top bight strip, which construction is notonly stronger than an upright member without such integral bight strip,but which causes the guiding parts to act in unison in guiding theshank.

In operation, the opening through the housing being narrower at thebottom, the tendency of the hook jaw is to pivot forward and backwardabout a pivot point at or just below the bottom edge of the housing.When the wrench is gripping a pipe, there is a pressure on the hook jawpulling it in an outward direction and pulling the nut against thebottom side of the housing. It will be apparent then that the hook jawinclines one way or the other when gripping the pipe, and that as it isturned, the tendency of the hook jaw is to move forward over the heeljaw. The tongue 33 then bends inward toward its upright member, and theupright member moves toward the edge wall. The pressure of the nutagainst the underside of the housing increases at this time and isdistributed by the base 30 over a large area, since the base is ofmaterial thickness, preventing the nut from digging into the housing.

When pressure is released, the tongues cause the shank to be againcentered in the housing. It will be appreciated that there is somebending in the base. This is particularly apparent at the points 40which are narrower at the slots. The pads 41, however, remain fiat andabsorb the thrust from the nut.

This bending also assists in causing the shank to be returned to anupright position. As a matter of fact, it is contemplated that thetongues 33 and 37 could be eliminated, and the bending action of thebase relied on for maintaining the proper alignment. The tongues are tobe preferred, however, because they do assist in maintaining thealignment.

Having thus described the invention in an embodiment thereof, it isappreciated that numerous and extensive departures may be made therefromwithout departing from the function or scope of the invention defined inthe appended claims.

I claim:

1. A centering and guard spring for a wrench having a housing, a hookjaw having a threaded shank extending through the housing, and a nut foradjusting the hook jaw, comprising a spring steel base portioninterposed between the nut and the housing, a guide portion extendinginto the housing and having a curved portion conforming to the surfaceof the hook jaw shank, said base having an abutment surface extendingoutwardly from the junction of said base and said guide portions, and atongue extending outwardly from the guide portion into engagement withthe inner wall of the housing,

2. A centering and guard spring for a wrench having r a housing, a hookjaw having a threaded shank extending through the housing, and a nut foradjusting the hook jaw, comprising a spring steel base portioninterposed between an upper surface of the nut and a lower surface ofthe housing, a guide portion extending into the housing and having acurved portion conforming to the surface of the hook jaw shank, and atongue extending outwardly from the guide portion into engagement withthe inner wall of the housing, said tongue being joined to the guideportion adjacent the base, and the guide por- 1 tion being formed byspaced side strips integral with a bridging top strip.

3. A centering and guard spring means for a wrench having a housing, ahook jaw having a threaded shank extending through the housing, and anut for adjusting the hook jaw, comprising a pair of spring steel hookjaw shank and nut engaging members disposed on opposite sides of thehook jaw and each including a base portion of semi-circular formationand provided with a notch for the shank of the hook jaw, said baseportion being disposed between the nut and the housing, an upright hookjaw guiding portion curved transversely to engage the threaded surfaceof the hook jaw shank, each base portion having an abutment surfaceextending outwardly from the junction of said base and said guidingportions, and a tongue struck from the guiding portion of said memberand bent outwardly into engagement with the inside wall of the housing.

4. A centering and guard spring means for a wrench having a housing, ahook jaw having a threaded shank extending through the housing, and anut for adjusting the hook jaw, comprising a pair of spring steel hookjaw shank and nut engaging members disposed on opposite sides of thehook jaw and each including a base portion of semi-circular formationproviding spaced pads for contact with an upper surface of the nut andproviding a notch for passage of the shank of the hook jaw, said baseportion being disposed between the nut and the housing, and an uprighthook jaw guiding portion curved transversely to engage the threadedsurface of the hook jaw shank and having a tongue struck from saidmember and bent outwardly into engagement with the inside wall of thehousing, said base portion also being necked down between said pads andthe upright portion so that said pads are resiliently bendable relativeto said upright portion.

References Cited in the file of this patent UNITED STATES PATENTS1,734,734 Lawson Nov. 5, 1929 1,778,748 Bayrer Oct. 21, 1930 2,192,702Wright Mar. 5, 1940 2,496,799 Lanckton Feb. 7, 1950

